1. Field
The present disclosure relates generally to communication, and more specifically to techniques for transmitting information in a wireless communication network.
2. Background
Wireless communication networks are widely deployed to provide various services such as voice, video, packet data, messaging, broadcast, etc. These wireless networks may be multiple-access networks capable of supporting multiple users by sharing the available network resources. Examples of such multiple-access networks include Code Division Multiple Access (CDMA) networks, Time Division Multiple Access (TDMA) networks, Frequency Division Multiple Access (FDMA) networks, Orthogonal FDMA (OFDMA) networks, and Single-Carrier FDMA (SC-FDMA) networks.
The third generation (3 G) mobile communications system has adopted a Wideband Code Division Multiple Access (WCDMA) wireless air interface access method for a cellular network. WCDMA can provide high frequency spectrum utilization, universal coverage, and high quality, high speed multimedia data transmission. The WCDMA method also meets all kinds of Quality of Service (QoS) requirements simultaneously, providing diverse flexible two-way transmission services and better communication quality to reduce transmission interruption rates.
In order to protect user data and signaling information from being intercepted by unauthorized devices, the prior art 3 G mobile communications system can trigger Integrity Protection and Ciphering. Integrity protection is utilized for protecting Radio Resource Control (RRC) messages transmitted on Signaling Radio Bearers (SRBs), while Ciphering is utilized for protecting Radio Link Control Protocol Data Units (RLC PDU) transmitted on Dedicated Channels.
Radio Bearers (RBs) are “logical” data communication exchange channels, and are utilized for providing data transmission exchange to the user or for providing RRC layer control signal transmission exchange. SRBs are the RBs specifically used for transmitting RRC messages, and utilized for completing various RRC control processes, such as RRC Connection Management Procedures, RB Control Procedures, RRC Connection Mobility Procedures, and Measurement Procedures. Therefore, the messages sent on SRB are sporadic.
Moreover, take an RRC communications protocol specification established by the 3 GPP for example, after the integrity protection procedure is activated, every time the User Equipment (UE) or the network transmits signaling message, the UE or the network will add a Message Authentication Code for data Integrity (MAC-I), whose content is different for each signaling message. A legal UE or network can authenticate the accuracy of the MAC-I, and thereby accept the received signaling message when the expected MAC-I and the received MAC-I are the same or act as if the message was not received when the calculated expected MAC-I and the received MAC-I differ, i.e. when the integrity protection check fails.
Even between legal UE and network, occasionally or perhaps as a rare event, the received MAC-I does not match the calculated (expected) MAC-I. For example, false detection of a successful cyclic redundancy check (CRC) in the physical layer occurs. As another example, de-synchronization of input parameter(s) to the algorithm (e.g. COUNT, IK) between network and UE can occur.